Johnson is the defending champion at this week’s The Northern Trust, and he enters as the top-ranked player in the world and the leader in the FedExCup standings - albeit by only 83 points over Justin Thomas.

“I’m fired up all the time, I just don’t let you guys see it,” Johnson said after his practice round Wednesday. “You’ll never know. Obviously, I’ve got a lot of fire going inside of me, and there’s a lot of things that I want to do that I haven’t done. So, that keeps pushing me.”

Johnson’s four career playoff victories is tied for the most all-time, but he has never managed to take home the season-ending title - or the $10 million prize that comes with it. He entered the Tour Championship ranked third last year, but fell to fourth with his tie for 17th at East Lake.

“I think so, absolutely,” Johnson said when asked if the lack of a FedExCup title can become a blemish on a top player’s resume. “I think that the FedExCup has become a really big part of the Tour. It’s going to continue to just get bigger. It’s something that I really want to win. I can’t speak for all of the other guys, but if I don’t ever win one, I’ll definitely be disappointed.”

Johnson has three victories this season - his third consecutive season with at least three wins. He also leads the Tour in numerous categories. But he failed to claim a major title in 2018, which puts extra emphasis on closing his season on a strong note.

While a handful of top players, including Rory McIlroy, Rickie Fowler (injury) and Henrik Stenson chose to skip The Northern Trust during the busy closing stretch of the calendar, Johnson said he never considered taking another week off. He was off last week and has played in only 16 Tour events this season, so he needs to accumulate more starts and strong results.

“It’s definitely a big accomplishment,” he said of potentially winning the playoffs. “It’s something that I really, really would like to win. To be a FedExCup champion, it means that you obviously played really well in the playoffs but you had a great year, too. It’s something that is definitely on my list of accomplishments that I’d like to achieve.”

He would also like to win Player of the Year honors. While everyone acknowledges that Brooks Koepka is the clear leader at this point with his two majors in 2018, Johnson disagreed with Tiger Woods’ assessment on Tuesday that the award is all but tucked away in Koepka’s trophy case.

“I’m proud of the way I’ve played this year, for the most part,” said Johnson, who is coming off a tie for 27th at the PGA Championship two weeks ago. “I’ve had three wins, which is a really good season.

“Obviously, we’ve still got four more events to play and then the Ryder Cup, so it’s not over yet. It could still become a great season, depending upon how I play in the playoffs.”